Generally, an ignition temperature control apparatus of a gas water heater may comprise a heat exchanger, a combustion device, a controller, etc. The combustion device can cause a combustible gas to be combusted, and provide heat generated by the combustion to the heat exchanger, so as to change cold water into hot water.
However, if the temperature of the external environment decreases to a certain value, the ignition temperature control apparatus of the gas water heater is often damaged by frozen water in the heat exchanger or other parts.
In order to solve the technical problem, the prior art mainly takes following measures:
anti-freezing by emptying: a water drainage pipeline is provided in the ignition temperature control apparatus of the gas water heater, wherein if the temperature decreases to a certain value, the controller controls the ignition temperature control apparatus of the gas water heater to exhaust low-temperature water in the water inlet and outlet pipes and the heat exchanger to achieve the purpose of anti-freezing; this method requires a water drainage pipeline, and the structure is complex;
anti-freezing by electrical heating: an electrically heating rod is provided on the surface of the heat exchanger and/or the water inlet and outlet pipes; if the temperature decreases to a certain value, the electrically heating element is controlled for heating; in this method, since only the electrically heating element is independently used for heating, the heating is non-uniform, the anti-freezing effect is poor, and the electric energy consumption is high.
Moreover, in the prior art, the heat exchanger in the ignition temperature control apparatus of the gas water heater is at least partially made of copper. Since copper has a poor thermal inertia, i.e., the heat exchanger made of copper has a high temperature change rate when a certain amount of heat is applied thereto within a certain period, the heat exchanger made of copper has a large temperature fluctuation when being heated under the stop state, and will easily be damaged. On the other hand, since copper has a high thermal conductivity coefficient (377W/m*K), the heat dissipation is fast when the heat exchanger stops operating, so that the heat exchanger will be cooled within a short time; thus under a low environment temperature, the heat exchanger at least partially made of copper will be easily frozen within a short period of time.